Counting Quantitative Reasoning as a Teaching of Psychology Priority Neil Lutsky Carleton College, Northfield, Minnesota USA, Third International Conference on the Teaching of Psychology 13 July 2008

“One of the things that makes psychology unique is that it makes the whole scientific enterprise so clear.” Nicky Hayes, University of Bradford ICOPE 2002

“The fundamental goal of education in psychology, from which all the others follow, is to teach students to think as scientists about behavior.” Charles Brewer et al. (1993), Curriculum, Handbook for Enhancing Undergraduate Education in Psychology

The longer I have been teaching psychology, the less important I have come to believe the teaching of psychology to be!

The concepts and findings of psychology are incredibly useful in making sense of behavior in the real world. Nonetheless, there is something else we could be emphasizing in the teaching of psychology to help students confront the world knowledgeably. That something else reflects a central element of life and citizenship in the contemporary world: numbers. One of the great gifts we can give students is the ability to use quantitative reasoning. Presentation/Argument Overview

What QR habits of mind do students need to gain or strengthen? How can we reinforce QR when teaching psychology? Presentation Overview (continued)

The Shelf Life Problem Manning, Levine, & Collins (2007). The Kitty Genovese murder and the social psychology of helping: The parable of the 38 witnesses. American Psychologist, 62,

“It is a proud thing to say ‘I taught him’ and a wise one not to specify what.” -Jacques Barzun

Derek Bok (2005), Our Underachieving Colleges “...certain basic quantitative methods seem applicable to a wide enough range of situations to be valuable for almost all students.”

“Learn statistics. Go abroad.” -K. Anthony Appiah, Princeton University

US: National Numeracy Network, Great Britain: More or Less, grammes/more_or_less/defa ult.stm International Statistical Literacy Project, z/~iase/islp/home

As psychologists we believe in the power of numbers, the power of numbers to influence & the power of numbers to inform.

The Power to Inform: “Statistics can tell us things about the world that we could not imagine on the basis of our senses alone...The social world is unimaginably more complex than we can see directly from any subjective vantage point within it.” -Paul Seabright, Times Literary Supplement

Numbers in Newspapers of Record

Numbers in Newspapers of Record.

“It sort of makes you stop and think, doesn’t it?”

Know to Read to the end of the article! Recognize the strengths of a Random clinical trial vs. Case Method. Understand Statistical Significance. Appreciate the difference between a Single study vs. a Literature. What quantitative concepts would a reader need to know in order to make sense of this important article?

What do I mean by “QR” ? Quantitative reasoning is the power and habit of mind to search out quantitative information, critique it, reflect upon it, and apply it in one’s public, personal, and professional lives. -National Numeracy Network

What do the numbers show? How representative is that? Compared to what? Is the outcome statistically significant? What’s the effect size? Are the results those of a single study or of a literature? What’s the research design (correlational or experimental)? How was the variable operationalized? Who’s in the measurement sample? Controlling for what other variables? 10 QR Que stion s at the Rea dy:

How representative is that?

Examples and stories. “For instance is no proof.” [Old Yiddish Saying] Extremes: “Up to 50% off.” “Up to 36 hours...”

How might Styron’s experience not be representative of those of others suffering from depression?

“The deep, fundamental question in statistical analysis is: Compared with what?” -Edward Tufte

Is the outcome statistically significant?

“Chance is lumpy.” -Robert Abelson

“An article in a leading medical journal said...that Pargluva seemed to significantly increase heart attack and stroke risks.” Goldacre: Why do journalists so often present quantitative information poorly?

What’s the effect size?

New Diabetes Drug Poses Major Risks Washington Post, October 21, 2005 A new diabetes medicine...sharply increases the risk of heart problems...researchers reported yesterday....the analysis found those taking the drug had more than twice the risk of death, heart attacks, and strokes, and nearly triple the risk when all types of heart problems were included. New Diabetes Drug Poses Major Risks, Panel Says Review Finds FDA Overlooked Data on Life-Threatening Cardiovascular Effects of Pargluva By Rob Stein and Marc Kaufman Washington Post Staff Writers, Friday, October 21, 2005; A02 A diabetes medicine poised to win Food and Drug Administration approval sharply increases the risk of heart problems, strokes and death, researchers reported yesterday in an analysis that raises new questions about how the agency handles drug safety concerns.

Are the results those of a single study or a literature?

Ioannidis Review of Medical Research (Journal of the American Medical Association, 2005) Even carefully peer-reviewed studies in the medical literature may not be fully supported subsequently. Ioannidis’s research suggested that will happen about 32% of the time.

What’s the research design?

Students need to recognize: Not all research studies are experiments. Not all studies called experiments are true experiments.

“It was more of a ‘triple-blind’ test. The patients didn’t know which ones were getting the real drug, the doctors didn’t know, and, I’m afraid, nobody knew.” RCTs:

How was the variable operationalized?

Who’s in the sample?

Johns Hopkins Iraqi Casualty Study The Lancet Estimated 601,027 “deaths by violence”. “For the single most important category--the total number of deaths by violence during the war--the confidence interval ranges from 426,369 to 793,663. That means that we are 95% certain that the correct number is between those two...” “If statesmen were better at arithmetic, wars would be far fewer.” -Benjamin Franklin

Medical “Efficaciousness” vs. “Effectiveness”

Controlling for what other variables?

British epidemiologist, who with Bradford Hill, was asked to investigate the alarming increase in lung cancer cases in Britain after WWII. Interviewed lung cancer patients in 1949 and found that cigarette smoking was the strongest characteristic they shared. Went on to study 40,000 British doctors over 50 years. Found that cigarette smoking reduced the life span by an average of 10 years. Sir Richard Doll

What do the numbers show?

“It is easy to lie with statistics, but easier to lie without them.” -Frederick Mosteller

What can we as teachers of psychology do to promote QR habits of mind? Teach QR skills & values. Teach for generalization!

“Statistics and psychology have long enjoyed an unusually close relationship-- for they are inextricably bound together.” -Stephen Stigler (1999)

“Science is not a collection of facts, any more than opera is a collection of notes. It’s a process, a way of thinking, a method, based on a single insight--that the degree to which an idea seems true has nothing to do with whether it is true, and that the way to distinguish factual ideas from false ones is to test them by experiment.” -Timothy Ferris (1998)

How we present information. What we ask students to do. What we can do as teachers.

Be explicit about: ~ Whether a study represents itself or a literature. ~ The contexts or typicality of examples. ~ How terms and concepts in psychology are related to equivalents in public discourse. How we present information:

Preach: ~ Why we use numbers. ~ Why precision is important. ~ How we evaluate numbers. ~ How we can construct meaningful, principled, and effective arguments with numbers. How we present information:

“the purpose of statistics is to organize a useful argument from quantitative evidence using a form of principled rhetoric.” -Robert Abelson

Use findings from psychology to underscore the virtues of Q inquiry. ~ Cognitive heuristics: Lawson et al. (2003), Teaching of Psychology. ~ Misperceptions of chance: ~ The psychology of belief.

Show how psychology has contributed to QR. ~ Measurement and its Q evaluation. ~ Effect size and meta-analysis.

Two-minute papers/Exam Qs: ~ Interpret a graphic, table, or numerical finding. ~ Identify key questions that could be raised about a quantitative finding. What we ask students to do:

Ask students to write with numbers. ~ Beins (1993), Teaching of Psychology. ~ Miller (2004), The Chicago Guide to Writing about Numbers.

“Even for works that are not inherently quantitative, one or two numeric facts can help convey the importance or context of your topic.” -Jane Miller, The Chicago Guide to Writing about Numbers

-from a review by Tim Flannery of Claire Nouvian’s The Deep, The New York Review of Books, 12/20/07. Only the uppermost part of the oceans--the top two hundred meters--bears any resemblance to the sunlit waters we are familiar with, yet below that zone lies the largest habitat on Earth. Ninety percent of all the ocean’s water lies below two hundred meters, and its volume is eleven times greater than that of all of the land above the sea... Below six thousand meters lies a region known as the hadal zone...; in the Marianas Trench off the Philippines it is 11,000 meters deep. Ships plying the waters over the trench glide as far above the Earth’s surface as do jet aircraft crossing the face of America.

Few (12%) of the papers for which QR peripherally relevant in fact used numbers. Many students rely on weasel words (e.g., “few”, “many”). Students assume staples convey meaning. QR terminology varies by discipline (e.g., “experiment”). QR Writing Assessment: The Quant Squad

Ask students to use numbers to set an instance in its wider context. How representative is this? For any case study assignment:

A radical notion illustrated: Research on Personality and Facebook Opening sentence: “Facebook is a wildly popular online social networking tool...” Revision: “Facebook is the Internet site most frequently viewed by males and females, aged 17-25, in the United States today (eMarketer, 2007). Sixty-nine percent of females and 56% of males in that age group have Facebook accounts; nearly 65% of users log on to Facebook once a day.”

How can students find relevant numbers?

Ask students to engage in quantitative inquiry. ~ /psych110_Lutsky/RMI/index.html *Measures FF Traits, happiness, background variables. *Readings: DeNeve (1999), Happy as an Extraverted Clam, Current Directions in Psychological Science, Text statistics appendix. *Learning goals: Ss think like psychological scientists, write with numbers, learn about meta- analysis.

“learners need to generate responses, with minimal cues, repeatedly over time with varied applications so that recall becomes fluent and is more likely to occur across difference contexts and content domains.” -Diane Halpern & Milt Hakel (2003)

“...numbers [are] the principal language of public argument.” More or Less, BBC News Programme

“…we teachers do not automatically deserve a future. We must earn it by the skill with which we disorient our students, energize them, and inculcate in them a taste for the hard disciplines of seeing and thinking.” -James O’Donnell, Avatars of the Word: From Papyrus to Cyberspace.